Method of and substance for treating tobacco smoke



Patented Feb. 22, 1938' UNITED STATES METHOD OF AND SUBSTANCE FOB TREAT- ING TOBACCO SMOKE Harold L. Kauflman, Warren, Pa, assignor of one-half to Paul Bechtner, Chicago, lllL' No Drawing. Application November 12, 1934, Serial No. 752,711

22 Claims. (W. 13131) This invention relates to improvements in methods of and substances for treating tobacco smoke. More specifically, it relates to the treatment of tobacco smoke for the purpose of improving said smoke, for example, by removing therefrom all, or a desirable portion, of those substances which are injurious to the human system and which are disagreeable in taste and foul in odor to the smoker.

One object of my invention is to remove, during the act of smoking, all, or a desirable portion, of the, major injurious and distasteful ingredients in smoke produced by the incomplete combustion of tobacco, so that the smoker avoids the harmful efiects upon his health of such injurious ingreclients and finds the act of smoking more pleasing to his taste.

Still another object or my invention is to provide an improved method of treating, during the 20 act of smoking, tobacco smoke produced by the incomplete combustion of tobacco by: (1) mentholating, medicating, flavoring, perfuming, aromatizing or similarly treating said tobacco smoke during said act of smoking, for the purpose of improving the smoke by either making it more healthful or more satisfactory to the smoker, or more pleasing andeppealing to the individual smokers senses of taste and smell than the smoker previously has experienced when drawing into 30 his mouth and his-system tobacco smoke which had not been so treated; and (2) concomitantly removing from said smoke all, or a desirable portion, of the major injurious and distasteful ingredients (e. g., nicotine, tobacco oils) present therein, so that the smoker avoids the harmful effects upon his health of such injurious ingredients.

In my co-pending application Serial No. 718,- 246, filed March 30, 1934, which application like wise relates to improvements in methods of treating tobacco smoke, I stated that I had found that tobacco smoke was more efiectively improved by introducing an oil-decolorizing-clay substance (e. g., fullers earth), in cigars, cigarettes, pipes, etc., between the point of combustion and the mouth of the smoker, whereby all, or a desirable portion (depending upon the amount of oildecolorizing-clay substance employed and its efficiency) of those substances which are disagree- 5 able in taste and foul in odor to-the smoker are removed from the smoke, more especially so when such substances are in the form of condensates, but also when they are in the form of vapors. In other words, the practicing of the invention disclosed in my co-pending application Serial no,

718,246 resulted in a-more effective treatment of tobacco smoke than previously had been known to the art.

I have now found, as a result of furtheriabora- 'tory work and practical experimentation, that oil-decolorizing-clay substances (e. g., fullers earth) are not the only substances which may be employed effectively in the treatment of tobacco smoke; and that-tobacco smoke may be treated equally as efiectively, and in many instances even more effectively (which latter is especially true when the tobacco smoke that is being treated isthat which results-from the incomplete combustion of tobacco of relatively high nicotine content) by the use of still another class of substances, namely, by the use of bentonitic-type clayey substances which, it in the form or state in which they are found in nature are not resistant to the disintegrating action or to the swelling action of moisture or water, are calcined at such a temperature and for such a period of time as to make them hard and resisting to the action of water and to destroy (if they are not already substantially non-colloidal as found in nature),

partially or completely, their natural colloidal iorm or structure. Practical smoking tests have shown that the use of a bentonitic-type clayey substance (calcined, when'necessary, as immediately hereinbefore described), when employed in the quantity and in the manner that hereinafter will be described, improved the taste of the tobacco and added to the enjoyment of smoking.v This improvement in the taste of the smokeis believed to be due to the removal from the smoke, by the said bentonitic-type clayey substance, of noxious substances (e. g., nicotine and other nitrogenous substances, tobacco oils, et cetera) as they are formed and the elimination thereby, when using pipes and cigar and cigarette holders, of the formation of tarry and gummy deposits, etc., in the bowl and stem of the pipes, and in the stems of cigar and cigarette holders;

I have found that a bentonitic-type clayey substance such as calcined bentonite (e. g., calcined Wyoming bentonite) has a greater aflinity for nicotine, and compounds and derivatives thereof,

than that possessed by most of the oil-decolorizing-claysubstances (e. g., Floridafullers earth). I have also found that just as the power or capacity of commercial fuller's earth to decolorize oils is improved from. to 50%, or more, by proper calcining operations, for example, by heating at 600 to 900 F. for from 15 to minutes, so too is the power or capacity of bentonite-type layey substances (e. g., bentonite) to remove noxious substances from tobacco smoke improved by proper calcining operations; for example, bentonites calcined at 1000 to 1400" F. for from 10 to 30 minutes were found to be from 10 to 50% more emcient in removing nicotine and other noxious substances from tobacco smoke than, noncalcined bentonites such as non-calcined Wyoming bentonite which, in that form or state, is highly colloidal and has the property of forming a gel with water. Some of the advantages in the use of a calcined bentonite over the use of a colloidal silicate for example (non-calcined bentonite, the use of which for the treatment of tobacco and tobacco smoke being old in the art, are mentioned immediately hereinafter: (1) less of the substance is required for the obtainment of the same degree of purification of the tobacco smoke, and it is therefore more economical to use; (2) assuming that the amounts employed are the same, use of a calcined bentonite improves the purity of the smoke by from 10 to 50% over and above that obtained by the use of a non-calcined or colloidal bentonite; (3) greater ease in drawing the smoke into the mouth and in keeping the tobacco burning when a calcined bentonite is employed, as compared with a colloidal or non-calcined bentonite, since colloidal silicates such as colloidal bentonite, in the presence of water, either disintegrate to a mud or swell many times their volume, thereby making it extremely dimcult and in many instances utterly impossible to draw the smoke through the same; for instance, when an attempt is made to use a noncalcined bentonite in pipes, the moisture from the mouth and from the tobacco reduces said bentonite to a pasty mass which clogs the bottom opening of the bowl and the stem of the pipe and makes it impossible to draw the smoke therethrough; (4) granules of colloidal or non-calcined bentonite, which, depending upon their origin, either disintegrate or swell in the presence of moisture or of water, are transformed by a suitable calcining operation into hard, stable, water-resisting granules or masses and the field of utility of said substance in, for example, the treatment of tobacco or of tobacco smoke is thereby greatly increased. For these and for other reasons, calcined bentonitic-type clayey substances are agents of superior quality for use in the treatment of tobacco smoke. I have also found that diatomaceous earth (kieselguhr) is of almost no value in removing such noxious substances as nicotine and tobacco oils from tobacco smoke; and that silica gel, although possessing some value for the removal of nicotine, is not so efiicient. as bentonitic-type clayey substances such as calcined bentonite in removing these harmful impurities and, furthermore, does not possess the power or capacity to remove tobacco oils from tobacco smoke that is possessed by, for example, calcined bentonite. Calcined bentonite as thus employed is an adsorbent and/or absorbent of both alkaloids and oily substances (such as tarry compounds and the like), and it is the removal of these noxious substances from the tobacco smoke by the use of bentonitic-type clayey substance, such as calcined bentonite,.

which is responsible, I believe, for the fact that tobacco smoke when brought into contact with such a substance is milder, less irritating, and more. pleasing to the taste than tobacco smoked without any treatment whatsoever en route to the mouth or when treated by being brought into intimate contact with colloidal silicates having the property of forming a gel with water, such as colloidal, non-calcined Wyoming bentonite, or

with any of the other substances heretofore known to the art.

I use the term bentonite-type clayey substance herein as a generic term which includes the well-known clayey substance bentonite", as well as other clayey substances and clay-minerals which are like, similar to or related to bentonite. "Bentonite-type clayey substance" and bentonitlc-type clayey substance are used by me synonomously. I include within the term hen-- tonite-type clayey substance" clay-minerals such as montmorillonite, beidellite, leverrierite, smectite, nontronite, halloysite, pyrophylllte, leucite, allophane, indianaite, otaylite, and the like; also, altered volcanic ashes, tuil's, breccias, pyroclasts and the like; and similar clayey substances that are like, similar to or related to bentonite, or that have physical properties and/or chemical characteristics like or similar to the clayey substance commonly designated and defined as bentonite. It is pointed out that a bentonite-type clayey substance" is a substance that is separate and distinct from an oil-decolorizing-clay substance, which latter name is used by me as a generic term in my co-pending application Serial No. 718,246; also, that bentonite is a clayey substance which is separate and distinct from fullers earth (a specific type of oil-decolorizing clay substance), That is to say, it is pointed out that neither fullers earth and bentonite nor oil-decolorizing-clay substance and bentonite-type clayey substance are equivalents. It is to be understood, however, that there is included within the scope of this invention the use of any natural clayey substance, or any clayey substance that has been heat-treated or other wise treated, or any synthetically prepared siliceous substance which is the equivalent of calcined Wyoming bentonite, Wyoming bentonite being representative of the colloidal silicates having the property of forming a gel with water.

Bentonite is defined and its general characteristics and composition are given in the following publications: Bentonite: Its Properties, .Mining, Preparation and Utilization, by C. W. Davis and H. C. Vacher, published in 1928 by the U. S. Bureau of Mines as Technical Paper 438; Bentonite, by Hugh S. Spence, published in 1924 by the Canadian Department of Mines as Publication No. 626; Possible Industrial Applications of Bentonite, by Hugh S. Spence and Margaret Light, published in 1931 by the Canadian Department of Mines as Publication 723-2; The Minerals of Bentonite and Related Clays and their Physical Properties, by C. S. Ross and E. V. Shannon, published in 1926 in the journal of the American Ceramic Society, volume 9, pages 77-79. Bentonites found in Wyoming are generally characterized by their marked swelling and dispersion when placed in water. In the art, such bentonites are very commonly referred to and designated as "Wyoming bentonite," or Wyoming-type bentonite, or gel-type bentonite. To identify commercial bentonites and to separate them according to their properties, Davis and Vacher classify bentonites as follows (Bureau of Mines Technical Paper No. 438, Bentonite: Its Properties, Mining, Preparation and Utilization, page 21): Alkali bentonite; alkali subbentonite; alkali-earth bentonite; and alkaliearth subbentonite.

Davis and Vacher say that most oil-refining clays are in this (alkali-earth subbentonite) class, which sentence is definitely and decidedly not true, if interpreted literally by itself. The

I ing clays) are in the alkali-earth subbentonite class. This is here pointed out in order to differentiate clearly between the invention herein disclosed, namely, the use of bentonite-type clayey substance in the treatment of tobacco smoke and the invention disclosed in my co-pending application Serial No. 718,246, which relates to the treatment .of tobacco smoke with an oil-decolorizingclay substance (e. g., fullers earth). No bentonite-type clayey substance that has been activated by, for example, treatment with a mineral acid and washing out the'excess acid and the products of the reaction, for the purpose of making a bleaching clay of the activated type therefrom,'is employed by mein the practicing of this invention. The use of such activated bleaching clay, which is a specific type of an oil-decolorizing-clay substance, was disclosed byme in my co-pending application Serial No. 718,246; use of such substance for the treatment of tobacco smoke is therefore considered by me to be outside the scope of the invention herein disclosed. I do, however, consider tobe new and novel, and to be within the scope of this invention, the use, after a suitable-calcination, of non-activated bentonites, that is, bentonites (such as alkali-- earth subbentonites), in non-activated form or state, and which, in that state. are unsuited for use in the decolorization of oils but which, by proper treatment, can be transformed into oildecolorizing-clay substances of the activatedbleaching-clay type or kind. The use of calcined alkali bentonites, alkali subbentonites and alkaliearth bentonites as agents for the treatment of tobacco smoke is'likewise considered by me to be within the scope of this invention.

In practicing my invention, I contemplate the use of bentonite-type clayey substances obtained from any of the known United States and foreign deposits of such substances or from any deposits not now known but which later may be found. I contemplate the use, after a suitablecalcination treatment, of, for example, bentonite from any of the known United States and foreign deposits of bentonite described on pages 4 to 8, inclusive, of Bureau of Mines Technical Paper No. 438, Bentonite: Its Properties. Mining. Preparation and Utilization, by C. W. Davis and H. C. Vacher; and on pages 5 to 11, inclusive, of Canadian Department of Mines Publication No. 626, ,Bentonits. by Hugh S. Spence: and on pages 93 to 95, inclusive, of Non-Metallic Minerals: Occurrence, Preparation and Utilization, by Raymond B. Ladoo, published in 1925 by Mc'Graw-Hill Book Company, Inc., of New York city, N. Y. As will be noted from a reading of the publications cited, bentonite is found in the United States in' the following States: Wyoming. California, South Dakota, Montana, Arizona, Utah, Texas, Tennessee, Idaho, New Mexico, Kentucky, Alabama,

Ohio, Nevada, Mississippi, Arkansas, Washington, Oregon, Kansas, Oklahoma, Louisiana, Minnesota, Wisconsin, Virginia and Pennsylvania. -At

capable of forming a gel with water.

. different substance from the It diifers somewhat suitable calcination treatment, is therefore contemplated in the practicing of this invention.

For illustrative purposes, one method of practicing my invention is hereinafter described: Into the bowl of a pipe, for example, is placed a small amount of granular bentonite-type clayey substance such as calcined bentonite. At this 'point'it may be well to mention that if the particular bentonite-type clayey substance (e. g., bentonite) is of the type which either disintegrates or swells in the presence of water in liquid or in'vapor form, said clayey substance is always initially calcined prior to use at such a temperature and for such afperiod of time (all as hereinafter will bev described) that it is made hard and resistant to the disintegrating or dispersing action of water. The calcination treatment, if desired, may be so conducted that the colloidal properties of the starting substance are substantially completely destroyed, in which case the end-product of the calcination treatment is substantially non-colloidal; or, if desired, the calcination treatment. may be so carried out that the colloidal properties of the starting substance are ,only partly destroyed, in which case the end-product of the calcination treatment may properly be regarded and described as a semi-colloidal substance or, more particularly, as a semi-colloidal adsorbent silicate. In all instances, however, the calcination treatment is so conducted that the physical characteristics of the starting substance are substantially altered or changed; and in all instances, too, the

end-product of the calcination treatment is in- For convenience, the residue from the calcination of a bentonite-type clayey substance such as bentonite is herein designated as a calcined bentonite, without differentiating as to whether or not said residue. is a substance of non-colloidal properties or of semi-colloidal properties. It is emphasized and here pointed out that the residue of the calcination treatment is, in all cases, a substance that has few, if any, of the distin guishing characteristics by which bentonites are commonly identified and-that it is a substantially cined bentonite.

Continuing the description of an illustrative method of practicing my invention: The granules of, for example, calcined bentonit-e that are placed in the bowl of the pipe must be sufilciently large as not to clog the bottom opening of the bowl and the stem of the pipe. With most pipes, I have found that calcined bentonite reduced in size so that most of it will pass through a U. S. Standard 4-mesh sieve but will be retained on a -U. S. Standard IO-mesh sieve is of a suitable size. However, calcined bentonite. coarser than mesh fineness may be used if desired, as well as calcined bentonite finer than mesh providing, in the latter case, the bottom opening of the bowl of the pipe is of such size, or is so fitted with ascreen, or is otherwise so designed that the bentonite will not clog the opening. The amount of calcined bentonite required to obtain the results herein'before stated varies with the quality of the tobacco and the smokinghabits of the individual smoker. However, I have found that using a pipe with a bowl of average size and for the average smoker, the use of from 0.1 to 2 parts by weight, for example, about 0.5 part, of granular, calcined bentonite (e. g., granular, calcined, Wyoming bentonite) to 1 part by weight of to bacco placed in the bowl is an amount suflicient starting or non-calfor the obtainment of the results desired. More of the said bentonite-type clayey substance than the amount stated may be used, if desired, providing that it is suiliclently coarse that the smoke may be drawn easily throughthe same by the smoker. It is important that the bottom opening of the bowl of the pipe be covered by the bentonite-type clayey substance. With the pipe of average size, at least about 0.2 gram of bentonite-type clayey substance such as calcined bentonlte is necessary to accomplish this result and, preferably, from about 0.4 to about 0.8 gram, or thereabove, is employed. Having placed the said granular, calcined substance in thebowl of the pipe, the pipe is packed with smoking tobacco and is smoked in the usual manner.

When the pipe-smoker has finished smoking his pipe, all, preferably, of the bentonite-type clayey substance is emptied from-the pipe together with ashes from the tobacco. The bentonite-type clayey substance (e. g., calcined bentonite) may be allowed to remain in the pipe and may be re-used, if desired, which practice many smokers prefer to follow; but, generally, more effective results are usually obtained if the calcined bentonite, or similar substance that is used,

is discarded and a fresh quantity is employed in the pipe each time tobacco is smoked therein.

The following are among theresults which I obtain by the-use of a granular, bentonite-type clayey substance such as granular, calcined hen-r tonite in pipes during the act of smoking: (1) a large part of the moisture content normally present in tobacco smoke is removed therefrom before the smoke reaches the mouth of the smoker; (2) virtually all of the moisture that may pass from the smokers mouth through the pipe stem to the heel of the pipe bowl is adsorbed and/or absorbed by said substance; (3) the pipe is kept clean; (4) the need for frequent use of cleaners is eliminated; (5) foul Juice is prevented from being drawn into the mouth; (6) the substance helps to keep the pipe sweet; (7) the substance, especially when treated, (e. g., mentholated) as hereinafter will be described, tends to make the smoke,cooler, which means that there is less tongue burning; (8) it improves the smoking qualityof a pipe by improving the pack and making proper drawing or ventilation virtually certain; (9) by keeping the pipe clean it permits the tobacco smoke to be drawn fresh and untainted through the stem; (10) it makes pipe-smoking more economical by eliminating the need for much of the wasteful, unsmoked heel in every pipeful of tobacco; (11) it eliminates, wholly or partially, depending upon the quantity of bentonite-type clayey substance employed, nicotine and other noxious impurities that are-present in tobacco smoke and which, when not removed therefrom, enter the human system and are injurious to the health of the smoker; (12) it prevents a pipe from becoming objectionable, on account of stale or foul odor, either to the smoker carrying it or smoking it, or to others; (13) it makes emptying a pipe easier, and no digging or prying with a sharp instrument is necessary to remove an unburned residue or heel.

When the bentonite-type clayey substance (e. g., calcined bentonite is white before being contacted with tobacco smoke, for example, be fore being placed in the bowl of a pipe prior to the smoking of tobacco therein, and if the said white, starting bentonite-type clayey substance is removed from the pipe (after smoking the tobacco in the pipe) and visually examined, it will be noted that the grains of said bentonite-type clayey substance have changed from their original white or. creamish white color to yellow, dark yellow, brown and even dark brown, depending upon the quality of the tobacco and the type and amount of bentonlte-type clayey substance that was employed. The change in color of the starting substance is a visual indication of the adsorption and/or absorption of nicotine, tarry compounds and other noxious substances from the tobacco smoke by the said substance. When the starting bentonite-type clayey substance is yellow in color, this visual indication of the removal of noxious substances from the tobacco smoke'by said bentonite-type clayey substance is somewhat obscured because of the original color of the starting substance.

Although this invention is particularly applicable to the treatment, during the act of smoking, of tobacco smoke resulting from the incomplete combustion of tobacco in pipes, it is not limited thereto; for it is equally applicable to the treatment, during the act of smoking, of tobacco smoke resulting from the incomplete combustion of tobacco regardless of the form or device employed in using it. Although most eflective results are generally obtained when the major part of. the smoke is brought into contact with the bentonlte-type clayey substance before it reaches the mouth of the smoker, this invention is not limited thereto, since various means may be employed for the obtainment-of the results desired; for example, if desired, the bentonite-type clayey substance may be incorporated, in various ways, with the tobacco at any stage of a process of treating tobacco prior to the use of the same by smokers, for example, at any stage of a process of treating cigarette tobacco prior to the use of the samein the manufacture of cigarettes.

As illustrative of a modification of my inventlon, I mention the following: In that end of cigars and cigarettes which smokers place in their mouths, I place a small amount of, for example, calcined bentonite in granular form. The bentonlte may be in contact directly with the tobacco, but, preferably, it is embedded in a pad of porous waddlng (for example, a waddlng made from cotton or other vegetable pulps or fibers) or placed in a cartridge of suitable design. Such an amount of bentonite-type clayey substance (e. g., calcined bentonite) is employed as will insure the results desired, tobaccos of inferior quality requiring the use of more bentonlte-type clayey substance than tobaccos of higher quality. in order to obtain the same degree of purification of the tobacco smoke. Any suitable amount of bentonite-type clayey substance may be employed. with certain -to-- baccos, as little as 2% by weight of the whole may be bentonite-type clayey substance (e. g., calcined bentonite) and will be eflective in the obtalnm'ent of the desired results; with other tobaccos, it may be necessary to use a percentage of bentonitetype clayey substance, by weight, equal to that of the tobacco, in which case the amount of bentonlte-type clayey substance employed is 50% by weight of the whole; or, when the starting bentonite-type clayey substance is of low elficlency or effectiveness as an agent for the treatment of tobacco smoke, an even larger amount of such substance may be required, possibly as much as 2 parts, by weight, of bentonite-type clayey substance for each 1' part of tobacco contained in the cigar or cigarette. For the most part, however, the use of from 0.02 to 1 part, by weight,

of bentonite-type clayeysubstance such'as cal- Or, if desired, the granular or powdered, treated cined bentonite to 1 part of tobacbo in'the cigar or cigarette is suflicient to effect the desired results. In the practicing of this particular modification of my invention I prefer to use granular bentonite-type clayey substance of finer mesh size than the hereinbefore-mentioned preferred mesh size for use in pipes; for example, bentonitetype clayey substance of such particle size that most of it (e. g., at least 80% of it) will pass through a U. S. Standard 10-mesh sieve but most of it (e. g., at least 80% of it) will be retained on a U. S. Standard l00-mesh sieve, or bentonitetype clayey substance of any intermediate particle size (e. g., commercially sized bentonite-type clayey substance of 16/30 mesh particle size, or of 30/60 mesh particle size, or of 60/80 mesh particle size, or of 60/100 mesh particle size, or 1 of 80/100 mesh particle size). The particle size is important in securing maximum efiectiveness from the bentonite-type clayey substance (e. g.,

calcined bentonite) in removing noxious substances from the tobacco smoke. In general, the more finely the bentonite-type clayey substance is comminuted, the more efiective it is in the obtainment ot the desired results. However, in practicingv this modification of my invention, the use of bentonite-type clayey substance in too finely divided form (for example, material all of which passes through a U. S. Standard 100-mesh sieve) is not conducive to satisfactory results from a practical standpoint, because it tends to pack excessively and makes it more difficult for the smoker to draw the tobacco smoke therethrough. In all references to particle size that are mentioned herein, it is to be distinctly understood that the particle size as given refers to the size of the material as commercially prepared; and when it is stated that the bentonite-type clayey substance is reduced in size so that it will pass through one U. S. Standard sieve (e. g., a 10-mesh sieve) but will be retained on another U. S. Standard sieve (e. g., a 60-mesh sieve), the second of which has more openings to the square inch than the first, I refer to the sizing of the bentonite-type clayey substance on a commercial scale and not as the substance might .be sized in preparing laboratory samples. In the commercial preparation of bentonite-type clayey substance that would be graded as 10/60-mesh material, not all would pass through a. 10-mesh sieve but, for example, only about 80% might pass therethrough; and not all of the same substance would be retained on a 60-mesh sieve but, for example, only about 80% might be retained thereon.

As illustrative of another modification of my invention, I mention the following: A smokers mixture is made by'thorcughly intermingling and.

mixing smoking tobacco, of the kind or kinds now commercially made and sold (or a commercial smoking tobacco the specific formula or method for the preparation of which is old in the art), with a granular or powdered, treated (treated with a tobacco-treating substance as will hereinafter be described) or untreated bentonite-type clayey substance, such as a granular or powdered, treated or untreated, calcined bentonite. The granular or powdered, treated or untreated substance, for example, calcined bentonite, may be sprinkled into and thoroughly mixed with the smoking tobacco to be used for cigarette filling, or with the tobacco, in whatever form tobe used for pipe filling, or with cigarfillers, or with cigars,

cigarettes and pipes filled in the ordinary manner.

- the mouth of the smoker, and whereby there will be obtained the results that have hereinbefore been fully set forth and described. In preparing the smokers mixture hereinbefore mentioned,

any desired quantity of treated or untreated bentonite-type clayey substance such as treated or untreated calcined bentonite may be used, so long as asuilicient quantity is'employed to effect the desired results. In general, although not always, use of treated or untreated bentonite-type clayey substance such as treated or untreated calcined bentonite in a smokers mixture effects the same ultimate results which are obtained by the use of such a substance in a smokable unit wherein the said substance is so arranged or placed in said unit that all of the smoke must contact said substance before the smoke reaches the mouth of the smoker. An exception to this latter statement is when the smokable unit is a pipe.

Obviously, the bentonite-type clayey substance (e. g., calcined bentonite) may be incorporated with or brought into contact with the tobacco at any stage'in a process of preparing the same for use by smokers; and, hence, this modification of my invention is not limited to thoroughly intermingling and mixing smoking tobacco (of the kind or kinds commercially made and sold) with a granular or powdered, treated or untreated bentonite-type clayey substance (e. g., granular or powdered, treated or untreated calcined bentonite) for the purpose of making an improved smokers mixture and during the use of which in a smokable unit or in smokable form the noxious smoke by the said bentonite-type clayey substance that is a component part of the smokers mixture. I may bring the tobacco into contact with the bentonite-type clayey substance (e. g., calcined bentonite) at any suitable stage in a process of preparing the same for use by smokers.

In the manufacture of tobacco for smoking, it is necessary to cure the strong and harsh raw material before blending and mixingso as to modify its disagreeable taste and to make it mild. It is common practice to effect curing by ageing, or the same ultimate results may be obtained artificially by means of a renewed fermentation induced by heat and moisture, or by masceratlng the tobacco leaves in water acidulated with hydrochloric acid or with other acid, or by mascerating the leaves in water containing some other suit-' able chemical, and thereafter washing the tobacco leaves with pure water. I may contact the tobacco with bentonite-type clayey substance such as calcined bentonite at any stage before or after the process of curing, or during the process of curing, and using for this purpose any suitable [substances will be removed from the tobacco or during the process of curing not only results in an improvement in the quality of the tobacco resulting therefrom, but also provides an eifectlve means of recovering such valuable by-products' as nicotine and other compounds that are removed from the tobacco, in varying degrees, by the curing process. Since bentonite type clayey substance such as calcined bentonite is an adsorbent and/or absorbent of nicotine and other objectionable constituents of tobacco, a portion of which constituents are removed by or during the particular curing process employed, such obiectionable constituents are immediately adsorbed by the bentonite-type clayey substance such as calcined bentonite when said substance is in contact with the tobacco during the curing process or during any other process that may be employed during the treatment of tobacco for the purpose of improving its useful qualities; and subsequently may be recovered from the adsorbent by extracting with a suitable solvent, by distillation, or by any other suitable means, purified (when necessary) and thereafter employed for those purposes for which the same may best be fitted. Thus, for example, may nicotine be recovered during a process of treating tobacco for the purpose of improving the useful qualities of the tobacco. When relatively large amounts of bentonite-type clayey substance such as calcined bentonite are thus employed, the larger part of the excess clayey substance may be removed from the tobacco by any suitablemeans and at any convenient or suitable stage of the process prior to the incorporation of the tobacco in cigars and cigarettes or prior to the packaging of the commercial and salable tobacco for use by the ultimate consumer; but, preferably, the tobacco is not freed of bentonite-type clayey substance (e. g., calcined bentonite) to the point where there is present, in contact with the tobacco, less than-about 2% by weight of said clayey substance.

As hereinbefore mentioned, I may treat tobacco, at any convenient or suitable stage of a process of making it suitable for use by the ultimate consumer, with granular or powdered,

treated or untreated, bentonite-type clayey substance such as granular or powdered, treated or untreated, calcined bentonite. The use'of clayey substance in granular form. is generally to be preferred, since, in that form, the excess clayey substance is more easily removed from the tobacco; there is less mechanical loss of the clayey substance; the substances, such as nicotine and the like, that are adsorbed by the clayey substance are more easily recovered from said clayey substance; and the clayey substance is more easily and efllciently revivifled, e. g., by calcining, by extraction with suitable solvent or solvents, or by combined solvent-extraction and roasting processes, and thereby made suitable for re-use. I may use bentonite-type clayey substance such as calcined bentonite, and preferably in granular form, at any suitable stage of a process of drying, curing, fermenting, mixing, blending, flavoring, aromatizing, medicating, irradiating, or otherwise processing or treating tobacco. From the viewpoint of this invention. the important point is that there shall be intermingled or admixed with the tobacco, or otherwise in contact with the tobacco when it is in the state or form in which it is used by the ultimate consumer, such an amount of bentonite-type clayey substance such as calcined bentonite as will effect the obtainment of the hereinbefore-stated desired results more efllciently and/or more economically, or

otherwise in an improved manner, than previously has been possible by theuse of any of the substances heretofore known to the art.

It is here pointed out that by fgranular substance I mean a substance of such particle size that substantially all of it will be retained on a U. S. Standard Sieve Series No. 100sieve; that is to say, a substance of such particle size that substantially all of its will be retained on a U. S. Standard 100 mesh sieve. And by powdered or finely divided substance, I mean a substance of such particle size that substantially all of it will pass through a U. S. Standard Sieve Series No. 100 sieve; that is to say, a substance of such;

particle size that substantially all of it will pass through a U. S..Standard 100-mesh sieve, Thus,

. particle sizes coarser than 100 mesh; or I may use granular particles coarser than 100 mesh of substantially uniform particle size, It is emphasized and it is to be understood that all references to particle size represent the size or range of particle sizes as the same would be commercially prepared.

In many instances, the use of atreated (that is to say, treated with a tobacco-treating substance) bentonite-type clayey substance such as a treated, calcined bentonite causes even a further improvement in the tobacco smoke than is effected when an untreated bentonite-type clayey substance such as an untreated, calcined bentonite is employed; that is to say, by the use of such a treated substance the tobacco smoke is even further improved by reason of its contact with said treated substance and is made either more healthful or more satisfactory to the individual smoker or more pleasing and appealing to the individual smokers senses of taste and smell.

In the preparation of a treated, granular or powdered, bentonite-type clayey substance, for example, a treated, granular or powdered, calclined bentonite, I may treat said substance with a counter-irritant such as menthol, 3.6 diamino 10 methyl-acridinium-chloride, ethoxydiamino acridinium-hydrochloride', orthoxychinolin potassium sulfate, or with variousother substances having the power either to. lessen or to eliminate entirely irritation of the mucous membrane during the act of smoking; or I may treat the bentonite-type clayey substance (e. g., calcined bentonite) with other chemicals, for example with soluble chemicals such as ferric chloride, boracic acid, pectic acid, citric acid, malic acid, oxalic acid and the like, that will either neutralize the smoke or will otherwise make the smoke either more healthful or more enjoyable to the smoker.

. Alkaline chemicals, in the treatment of certain the incomplete combustion'of the tobacco. Or, I may treat the bentonite-type clayey substance with yeast in an amount-varying from about 1% to about 50% by weight of the whole to obtain,

for example, the results described by Calvin Hicks in- U. S. Patent Number 1,842,266, issued January. 19, 1932, for a tobacco mixture; or, I may treat the bentonite-type clayey substance (e. g., calcined bentonite) with a medicament (e. g., iodine) or, in order to improve the flavor or aroma or odor of the tobacco or of the smoke,

or otherwise to improve either the tobacco or the. smoke, I may treat bentoniteetype clayey sub- .stance such as calcined bentonite'with any 01' the tonite-type clayey substance such as calcined bentonite with glycerine, sugar, saccharine, licorice, synthetic fruit flavoring, caramel,

' mint, oil of sassafras, or with like or similar flavoring and/or perfuming and/or aromatic substances. I contemplate the treatment of bentonite-type clayey substance such as calcined bentonite not only with those substances with which tobacco is now commonly treated in order to improve the smoke resulting from. its incomplete combustion, such as counter-irritants, medicaments, flavoring and/or aromatic and/or per- 7 fuming substances, by the obtainmentoi the hereinbei'ore mentioned dairable results, but also with any other substance or substances not now knownto me but which will similarly im-' prove tobacco, and the smoke resulting therefrom when it burns, and which when smoked will prove more healthful or more pleasing, or both, to the smoker. As a generic term, and for convenience, I designate those substances with which tobacco is commonly treated as "tobaccotreating substances. I may apply to bentonitetype clayey substance such as calcined bentonite as little as a trace of one or more tobacco-treating substances or I may completely impregnate bentonite-type clayey substance such as calcined bento'nite with one or more of said substances, so that, after impregnation, as much as, for example, 60% by weight of the whole consists of tobacco-treating substance. When bentonitetype clayey substance such as calcined bentonite has been treated with a tobacco-treatingsubstance in any amount less than that which would completely iill the pore space of said clayey substance,- said substance still has power or capacity (the degree thereof depending upon the extent to which the pore space has been filled with tobacco-treating substance) to obviate the injurious influence of noxious substances, such as nicotine and tobacco oils, in tobacco smoke, by adsorbing and/or absorbing such substances. In the practicing of my invention I may treat bentonite-type, clayey substance such as calcined bentonite in the manner that has been set forth immediately hereinbei'ore, and then mix said treated bentonite-type clayey substance (e. g.,

treated, calcined bentonite) with a non-treated bentonite-type clayey substance (e. g., non-treated calcined bentonite) and thereafter use said mixture for such purposes as, for example, the treatment of tobacco, or for the treatment of tobacco smoke, or in the treatment of a smoking I a'ioaaco treating substance).

quantity of material is handled during the process of applying the tobacco-treating substance to the particular bentonite-type clayey substance,

easily controlled (that is to say, the blended or mixed clayey substances can be so varied that there will be present therein the exact desired amount. of a particular tobacco-treating substance or substances, whereby there is eliminated the possibility that the clayey substance as used may contain an obiectionable excess of tobacco:

ite-type clayey substance such as calcined bentonite whicl'ihas been treated with a tobacco- Obviously, I may use, however, it and when desired, a treated bentonite treating substance) in' the same manner for the 4 -treatment oi tobacco, or for the treatment of towater, since the Wyoming bentonites are able to adsorb many times, for example, as much as 5 times their weight of water, and some of them are capable of swelling as muchas 14 times their dry bulk. It is possible to mold plastic masses of some bentonite-type clayey substances and thereafter to dry and bake the molded material without its undergoing substantial cracking. In other instances it may be advisable, either before or after wetting, to mix the starting bentonitetype clayey substance (and especially when said substance is a bentonite) withothcr argillaceous substance, for example, with porous argillaceous substance such as oil-decolorizing-clay substance, andat any suitable or convenient stage prior to the molding step. The incorporation of such substance (e. g., fullers earth, which is a specific type of oil-decolorizing-clay substance) with bentonite-type clayey substance at any suitable point prior to the molding operation is therefore contemplated by me. I may use any suitable amount of oil-decolorizing-clay substance (a specific type of porous argillaceous substance) admixed with bentonite-type clayey substance. In certain cases, as little as 2% of such porous argillaceous substance will result in the obtainment of a molded product of suitable physical and other characteristics; in other instances, as much as 50to 60% andupwards of such porous argillaceous substance may berequired. In all cases,the amount of such porous argillaceous substance that is employed is largely dependent upon the physical and othr characteristics of the starting bentonite-type clayey substance. Or, as another means of obtaining a suitable molded bento'nite-type clayey substance, and especially when the starting substance is one-which is so colloidal (e. g.,' Wyoming bentonite) that it startingsubstance and so as to obtain a substance, which, when wetted with water, becomes of the exact degree of plasticity that I require for the subsequent molding operation.

porous argillaceous substance such as an 011- decolorizing-clay substance of the nature of fullers earth and the like) is then dried and thereafter baked at a suitable temperature and for a suitable time, in order to give it the required hardness and other physical characteristics. Although the molded and baked clayey substance is effective in removing noxious substances from tobacco smoke, the use of said clayey substance in that form usually neces"sitates, for ease of drawing the smoke therethrough, that the mass be perforated, that is, have a number of holes therein, if made in the shape of, for example, a thin disc or plate of a size suitable, for example,

. for use in pipes; or that it be formed into a tubular or similar shape for more convenient use in, for example, the stems of pipes, cigar or cigarette holders. If in cylindrical shape, the mass of baked clayey substance may have only one hole therein; or two, three, four, or a half dozen or more holes of any desired diameter may be made therein (the holes being made, preferably, during the molding operation), since the greater the surface area exposed to the substance, for example, tobacco smoke, to be treated, for example, purified (as in the removal of noxious substances from tobacco smoke), the more rapid and complete will be the adsorption and/orabsorption of such noxious substances contained in the smoke by the molded and baked clayey substance of the kind or kinds hereinbefore fully set forth and described. If desired, all or a part of the stem and the bowl of the pipe may be made of molded and baked clayey substance of the kind or kinds herein stated; for example, the bowl of the pipe may have an inner lining of such clayey substance or a section or a part of the stem of the pipe may be made of said substance. In all such cases the design of the pipe is such that the tobacco smoke comes into intimate contact with that portion of the pipe which is made of the kind or kinds of clayey substance hereinbefore described, and which clayey substance had been molded to the desired form or shape and then baked to give it suitable hardness, strength and moisture-resistance. .The molded and baked clayey substance may be used, for example, in the treatment of tobacco smoke in the manner hereinbefore described, or it may be impregnated with a tobacco-treating substance of the kind or kinds hereinbefore described, at any stage of a process of making a molded and baked clayey substance of the kind or kinds herein described, or after thesame has been made, all as hereinbefore fully set forth. The treated, molded and baked clayey substance of the kind or kinds herein described then may be used as desired, for example, in the treatment of tobacco smoke as hereinbefore stated, or for the treatment of tobacco; and, in general, said treated substancemay be used for the purposes and to effect the results that likewise hereinbefore have been explained at some length.

If theparticular bentonite-type clayey substance (e. g., bentonite) is of the type which either disintegrates or swells in the presence of water in liquid or in vapor form, said clayey substance is always initially calcined prior to use at such a temperature and for such a period of time that it is made hard and resistant to the disintegrating or dispersing action of water. The calcination treatment, if desired, may be so conducted that the colloidal properties of the starting substance are substantially completely destroyed, in which case the end-product of the calcination treatment is substantially non-colloidal; or, ii desired, the calcination treatment may be so carried out that the colloidal properties of the starting substance are only partly destroyed, in which case the end-product of the calcination treatment may properly be regarded and described as a semi-colloidal substance or, more particularly, as a semi-colloidal adsorbent silicate. In all instances, however, the calcination treatment is so conducted that the physical characterlstics possessed by the starting substance are substantially altered or changed; and, in all instances, too, the end-product of the calcination treatment is incapable of forming a gel with water.

The fact that the colloidal properties of colloidal clays such as Wyoming bentonite could be destroyed by heat treatment has long been known to the art and I make no claim to the same. Reference is here made to Bureau of Mines Technical Paper 438, Bentonite: Its Properties, Mining, Preparation, and Utilization, by C. W. Davis andH. C. Vacher, page 18, wherein these authors say, under a discussion of the properties of bentonite: Loss of colloidal properties on heating-A small portion of minus IO-mesh material (bentonite) was put into a porcelain crucible and heated in an electric muifle (furnace). The temperature was raised at intervals of 50 C., and the samples allowed to remain 24 hours at each temperature. After each heating small samples were placed in test tubes of water and shaken. Below 350 C. (662 F.) all the samples absorbed water. Sample 12 lost its colloidality (was no longer affected by water) at 410 C. (770 F.) sample 10,

at 510 C. (950 F.); sample 9, at 575 C. (1067 F.); and sample 11, at 670 C. (1238 F.) Regulated heat treatment differentiates the types of bentonite in the same order as swelling in water; that is, the less the swelling in water, the lower the temperature at which colloidality is destroyed. Similar effects are obtained by calcining the particular starting colloidal silicate at higher temperatures for shorter periods of time. Thus, in order to destroy partly or substantially completely the colloidality of a colloidal clayey substance such as bentonite, I may calcine said substance at temperatures ranging from about 700 F. to about 1500 F. for periods of time ranging from about 8 minutes to about 8 hours. Obviously, the particular end-temperature and time of heating that I employ is influenced greatly by the degree of colloidality possessed by the starting bentonite and the extent to which I desire to destroy that colloidality by said calcination treatment. From a practical standpoint, that is to say, forthe purpose of economy of operation or for other purposes, it may often be advantageous to calcine the starting substance relatively rapidly at increasing temperatures ending above 1500 F., and, for periods of time ranging from about 4 seconds to about 8 minutes. I therefore contemplate the use of temperatures, when it seems advisable so to do, in excess of 1500 F., for example, temperatures ranging from between about 1500 F. and about 2000 F., or thereabove, and for very short periods of time, in consequence of which the physical characteristics of the starting substance are quickly altered or changed as hereinbefore fully set forth and described. Any suitable apparatus or equipment may be employed for the calcination treatment. As hereinbeiore stated, the end-product of the treatment is a substantially new product and has few, if any,

' of the distinguishing characteristics by which bentonites are commonly identified. Furthermore, itisa more efiective and/or more economical agent for use in the treatment of tobacco or tobacco smoke, by reason of, for example, itsgreater power or capacity to adsorb and/or absorb the noxious impurities that are commonly present in tobacco and in the smoke resulting therefrom, than colloidal silicates such as colloidal or non-calcined bentonite having the characteristic property of forming a gel with water; and, moreover, the end-product or -products of my calcination treatment have fields of usefulness inthe treatment of tobacco smoke not possessed by colloidal silicates such as colloidal or non-calcined bentonite, for example, my endproduct'may be used eifectively in pipes for the treatment of tobacco smoke. As hereinbefore mentioned, colloidal silicates are wholly unfitted for use in pipes, in the treatment of tobacco smoke, due to the fact that the colloidal substance either disintegrates or swells in the presence of moisture and wholly or partly clogs the bottom opening of the bowl and the stem' of the pipe. Those skilled in the art will therefore readily recognize the advantages that are obtained by the use of the substance immediately hereinbefore described, which substance is an end-product of the calcination treatment just described, and which is employed by me in the treatment of tobacco or of tobacco smoke as hereinbefore fully set forth and explained.

In accordance with the provisions of the patent statutes, I have hereinbefore described the best mode now known to me of carrying this in-' vention into effect; but I desire it to be distinctly understood that I fully realize that changes may be made therein and that I intend to include within the scope of the claims that follow hereinafter all modifications that do not depart substantially from the spirit of the invention set forth therein and thereby.

What I claim is:

1. The improved method of treating tobacco smoke resulting from the incomplete combustion of tobacco during the act of smoking, comprising bringing the tobacco smoke, between the burning tobacco and the mouth of the smoker, into contact with. an improved agent for the treatment of tobacco smoke that comprises the residue from the calcination of bentonite at temperatures ending above about 700 degrees F. and that is characterized by being hard, substantially resistant to the disintegrating action of water and possessive of selective adsorptive properties,

whereby noxious substances of the tobacco smoke are selectively adsorbed by .the said improved agent.

2. The improvement in a method of treating tobacco smoke resulting from the incomplete combustion of tobacco during the act of smoking, comprising bringing the tobacco smoke, between the burning tobacco and the mouth of the smoker, into contact with an improved agent, in granular form, for the treatment of tobacco smoke that consists of the residue from the calcination of bentonite at a temperature ending between about 700 degrees F. and about 1500 degrees F. and that is characterized by being hard, substan-' tially resistant to the disintegrating action of water and possessive of selective adsorptive properties, whereby noxious substances of the tobacco smoke are selectively adsorbed by the said improved agent in granular form. I

8. The improved method of treating tobacco smoke resulting from the incomplete combus-- tion of tobacco during the act of smoking, comprising bringing the tobacco smoke, between the burning tobacco and the mouth of the smoker,- .into contact with an improved agent for the treatment of tobacco smoke that comprises the residue from the calcination of bentonite at temperatures sufliciently high to destroy substantially completely the colloidality possessed by the starting bentonite and that is characterized by being hard, substantially resistant to the disintegrating action of .water and substantially non-colloidal.

4. The improvement in amethod of treating tobacco smoke resulting from the incomplete combustion of tobacco during the act of smoking, v

long to destroy a substantial part of the colloidality possessed by the starting bentonite, said improved agent being characterized by being hard, substantially resistant to the disintegrating action of ,water and possessive of selective adsorptive properties, whereby noxious substances of the tobacco smoke are selectively adsorbed by the said improvedagent.

5. The improved method of treating tobacco smoke resulting from the incomplete combustion of tobacco during the act of smoking, comprising bringing the tobacco smoke, between the burning tobacco and the mouth of the smoker, into contact with an improved agent for the treatment of tobacco smoke that consists of an intimate association of a tobacco-treating substance and the residue from the calcination of bentonite at temperatures ending above about 700 degrees F., said residue being characterized by being hard, substantially resistant to the disintegrating action of water and possessive of selective adsorptive properties.

6. The improved method of treating tobacco smoke resulting from the incomplete combustion of tobacco during the act of smoking, comprising bringing the tobacco smoke, between the burning tobacco and the mouth of the smoker, into contact with an improved agent for the treatment of tobacco smoke that consists of an intimate association of a tobacco-treating substance, which has the characteristic property of vaporizing upon the application of heat without substantial decomposition, and theresidue from the calcination oi bentonite at a temperature ending between about 700 degrees F. and about 1500 degrees F., said residue being characterized by being hard, substantially resistant to the disintegrating action of water and possessive of selective adsorptive properties.

7. The improved method ofv treating tobacco smoke resulting from the incompletecombustion of tobacco during the actof smoking, comprising atures ending above about 700 degrees F. and that t Characterized .by being hard, substantially resistant to the disintegrating action of water and possessive of selective adsorptive properties, whereby noxious substances of the tobacco smoke are selectively adsorbed by the said improved agent in molded form.

8. The improvement in a method of treating consists of the resultant from the calcination of a molded and dried admixture of fullers earth and bentonite-type clayey substanceat temperatures ending above about 700 degrees F. and that is characterized by being hard, substantially resistant to the disintegrating action of water and possessive of selective adsorptive properties, whereby noxious substances of the tobacco smoke are selectively adsorbed by the said improved agent in molded form.

9. The improved method of treating tobacco smoke resulting from the incomplete combustion of tobacco during the act of smoking, consisting in embedding in the smoking tobacco a quantity of an improved agent for the treatment of tobacco smoke that comprises the residue from the calcination of bentonite at temperatures ending above about 700 degrees F. and that is characterized by being hard, substantially resistant to the disintegrating action of water and possessive of selective adsorptive properties, and causing the smoke to contact with the said improved agent before reaching the mouth of the smoker.

10. The improvement in a method of. treating tobacco smoke resulting from the incomplete combustion of tobacco during the act of smoking, consisting in embedding in the smoking tobacco a quantity of an improved agent for the treatment of tobacco smoke that consists of the residue from the calcination of bentonite at a temperature ending between about 700 degrees F. and about 1500 degrees F. and that is characterized by being hard, substantially resistant to the disintegrating action of water and possessive of selective adsorptive properties, and causing the smoke to contact with the said improved agent before reaching the mouth of the smoker.

11. The improved method of treating tobacco smoke resulting from the incomplete combustion of tobacco during the act of smoking, consisting in embedding in the smoking tobacco a quantity of an improved agent for the treatment of tobacco smoke that consists of the residue from the calcination of bentonite at temperatures ending sufflciently above about 700 degrees F. and for a period of time sufiiciently long to destroy a substantial part of the colloidality possessed by the starting bentonite, said improved agent being characterized by being hard, substantially resistant to the disintegrating action of water and possessive of selective adsorptive properties, and causing the smoke to contact with the said improved agent before reaching the mouth of the smoker.

12. The improvement in a method of treating tobacco smoke resulting from the incomplete combustion of tobacco during the act of smoking, consisting in embedding in the smoking tobacco an improved agent, in molded form, for the treatment of tobacco smoke that consists of the residue from the calcination of molded and dried bentonite-type clayey substance at temperatures ending above about 700 degrees F. and that is' characterized by being hard, substantially resistant to the disintegrating action of water and possessive of selective adsorptive properties, and causing the smoke to contact with the said improved agent before reaching the mouth of the smoker. r

13. The improved method of treating tobacco smoke resulting from the incomplete combustion of tobacco during the act of smoking, consisting in embedding in the smoking tobacco an improved agent, in molded form, for the treatment of tobacco smoke that consists of the resultant from the calcination of 'a molded and dried admixture of fullers earth and bentonite-type clayey substance at temperatures ending above about 700 degrees F. and that is characterized by being hard, substantially resistant to the disintegrating action of water and possessive of selective adsorptive properties, and causing the smoke to contact with the said improved agent in molded form before reaching the mouth of the smoker.

14. The improvement in a method of treating tobacco smoke resulting from the incomplete combustion of tobacco during the act of smoking, consisting in embedding in the smoking tobacco an improved agent for the treatment of tobacco smoke that consists of an intimate association of a medicament and the residue from the calcination of bentonite-type clayey substance at temperatures ending above about 700 degrees F., said residue being characterized by being hard, sub-v stantially resistant to the disintegrating action of water and possessive of selective adsorptive properties, and causing the smoke to contact with the said improved agent before reaching the mouth of the smoker.

15. The process which comprises placing in the bowl of a pipe a quantity of an improved agent for the treatment of tobacco smoke that comprises the residue from the calcination of bentonite-type clayey substance at temperatures ending above about'ZOO degrees F. and that is characterized by being hard, substantially resistant to the disintegrating action of water and possessive of selective adsorptive properties, packing the pipe with tobacco in the usual manner, igniting the tobacco, and causing the smoke from the burning of the tobacco to contact with the said improved agent before reaching the mouth of the smoker, whereby the said improved agent selectively adsorbs noxious substances from the tobacco smoke, and herein set forth other results are obtained.

16. The process which comprises placing in the bowl of a pipe a quantity of an improved agent for the treatment of tobacco smoke of particle size as herein set forth, which improved agent consists of the residue from the calcination of bentonite at a temperature ending between about I degrees F. and about 1500 degrees F. and is characterized by being hard, substantially resistant to the disintegrating action of water and possessive of selective adsorptive properties, packing the pipe with tobacco in the usual manner, igniting the tobacco, and causing the smoke from the burning of the tobacco to contact with the said improved agent before reaching the mouth of the smoker, whereby the said improved agent selectively adsorbs noxious substances from the tobacco smoke and herein set forth other results are obtained.

17. Treatment of tobacco, comprising adding to tobacco the residue from the calcination of bentonite-type clayey substance at temperatures ending above about 700 degrees F., said residue being characterized by being hard, substantially resistant to the disintegrating action of water and possessive of selective adsorptive properties, and which product, upon the smoking oi. the tobacco, improves the tobacco smoke by selectively adsorbing noxious substances present therein.

18. Treatment of tobacco, consisting in adding to tobacco an improved agent ior the treatment of tobacco and tobacco smoke that comprises the residue from the calcination of bentonite at temperatures ending above about 700 degrees F. and for a period of time sufllcientiy long to diminish appreciably the colloidaiity possessed by the starting bentonite, said residue being characterized by possessing improved selective adsorptive properties, and which product, upon the smoking of the tobacco, improves the tobacco smoke by selectively adsorbing noxious substances present therein. V

19. A smokers mixture, comprising smoking tobacco and an improved agentfor the treatment of tobacco smoke that comprises the residue from the calcination at bentonite-type clayey substance at temperatures ending above about 700 degrees F. and that is characterized by being hard, substantially resistant to the disintegrating action of water and possessive of selective adsorptive properties, said improved agent being intermingled 01' tobacco smoke that consists of the residue from the calcination of bentonite at temperatures ending above about 700 degrees F. and for a period of time suflicientiy long to diminish appreciably the colloidality possessed by the starting bentonite, said residue being characterized by possessing improved selective adsorptive properties, and

said improved agent being intermingled with the water and possessive of selective adsorptive properties.

22. An improved agent for the treatment of tobacco smoke consisting of an intimate association of a medicament and the residue from the calcination oi bentonite at temperatures ending above about 100 degrees B, said residue being characterized by being hard, substantially resistant to the disintegrating action of water and possessive of selective adsorptive properties. HAROLD L. KAUFF'MAN. 

